The present invention relates to a method of making aromatic cyclic polyformals of the formula ##STR1## WHERE R is a divalent aromatic C.sub.(6-30) organic radical defined more particularly below and n is an integer equal to from 2-25 inclusive. More particularly, the present invention relates to the extraction of aromatic cyclic polyformal from aromatic polyformal formed by reacting a bisphenol dianion with a methylene halide.
An alternative method of making the aromatic cyclic polyformal of formula (1) is shown in copending application Ser. No. 905,637 of Donald S. Johnson, A Method For Making Cyclic Polyformals, filed concurrently herewith and assigned to the same assignee as the present invention. In Ser. No. 905,637, a phase transfer catalyst is used to effect reaction between an insitu formed bisphenol dianion in an aqueous phase with a methylene halide organic phase to directly produce aromatic cyclic polyformal of formula (1), substantially free of aromatic linear polyformal.
In copending application Ser. No. 905,637, of Allan S. Hay, for Cyclic Polyformals and Method For Making, also filed concurrently herewith and assigned to the same assignee as the present invention, cyclic polyformals of 2,2-bis(4-hydroxyphenyl)-1,1-dichloroethylene, or "dichloride", is described. Isolation of the cyclic polyformal of the dichloride is achieved by the use of a high pressure liquid chromatograph.